Combustion means



May 19, 1942.

E. J. wEsTcoT'r ETAL 2,283,658

COMBUSTION MEANS Filed Jan. 20, 1939 2 Sheets-Sheet 1 INVENTOR- Ellsworth J. M5100 t t v J0 nCHaye r,

May 19, 1942. E. J. WESTCOTT EI'AL 2,283,658

COMBUSTION MEANS v Filed Jan. 20, 1939 ,2 sheets-sheet 2 B z zs w rgh WZS QZ Z'E z BY 0 n 3 85 I? ATTTO Patented May 19, 1942 COMBUSTION MEANS Ellsworth J. Westcott and John (2. Hayes, Jr., Ghicago, Ill., assignors to Freyn Engineering Company, Chicago, 111., a corporation of Maine Application January 20, 1939, Serial No. 251,946

19 Claims.

The present invention relates to improvements in combustion means with particular reference to burners. The present invention will be described in connection with burners for boiler use, though as the description proceeds it will be apparent that the invention has a broader application.

An object of the present invention is to provide a burner well adapted for the use of blast furnace gas.

A further object is to provide a burner adapted for the combustion of furnace gas and air, so constructed that those portions of the burner which are subjected to damaging conditions are readily replaceable, whereas the other portions of the burner are of permanent construction.

A further object is to provide a burner well adapted for the combustion of blast furnace gas, or the like, andair, together with the combustion of auxiliary fuels of a different specific gravity than blast furnace gas.

A further object is to provide a burner well adapted for the combustion of blast furnace gas, or the like, and air, together with the combustion of atomized liquid fuel.

A further object is to provide a burner readily adaptable to varying furnace dimensions whereby most of the volume of the combustion chamber of the furnace may be usefully employed.

Further objects will appear as the description proceeds.

Referring to the drawings- Figure 1 is a top plan View, parts being broken away, illustrating one embodiment of the present invention, the sectional parts of Figure 1 being taken along the planes indicated by the arrows 1-! of Figure 2;

Figure 2 is a sectional view taken along the planes indicated by the arrows 2-2 of Figure 1; and

Figure 3 is a sectional view taken along the plane indicated by the arrows 3-3 of Figure 2.

The numeral It] indicates a boiler, or the like, embodying a combustion chamber having an opening H therein for the reception of a burner, which burner is indicated as a whole by the numeral l2. As illustrated in Figures 1 and 2, the burner I2 is elongated horizontally and includes a casing l3, which projects into the wall of the boiler. The top wall of the casing 13 is provided adjacent to the rear extremity thereof with the gas inlet it, which may admit blast furnace gas. I 'he bottom wall of said casing I3 is provided with the air inlet [5. Intermediate of the length of the burner I2 are the parallel vertical walls l6 extending from the top to the bottom of said burner l2. Pairs of said vertical walls l5l6 are united at their rear extremities by means of the slanting rear walls l1. Said vertical walls lB-IB and the slanting rear walls upperportion of the burner I2. Figure 2; the lower boundaries of said passageways 20-20 (at the outer ends thereof) are de-' I! provide chambers communicating with the air inlet l5. Said walls [6-46 at their forward extremities are provided with the angular members lS-IB, the horizontal contour of which is illustrated in Figure 1. Said angular members I8i8 form locating and holding means for refractory walls l9--l 9. .The air chambers defined by the vertical walls I i-I6 and the slanting wall I! are spaced apart and provide passageways Zll-ZU having communication'with the blast furnace gas inlet M. Said vertical walls lE-l6 and the slanting Wall I! therefore de-.

fine parallel passageways for blast furnace gas and for air. Said air and blast furnace gas are kept separated until they reach the forward extremity of the burner. I I

As illustrated in Figure 2, the passageways Ell-29 for the blast furnace gas occupy only the As shown in fined by the refractory members 2l2|, which extend from the members Iii-48 to the forward extremity of the burner. Rearwardly of said members IB-l8, the lower extremities of the paths for blast furnace gas are defined by the wall 2m extending from the rear of the casing l3 to the members |8l8, being fitted around the chambers provided by the vertical walls Iii-l6 and the slanting rear walls llil. Said refractory members 2 l-2| are provided with the axial bores 22-42, Passageways leading to said bores 22-22 are provided by the metallic cylindrical members 23, which extend from the rear wall of the casing l3. At'the rear of the burner and communicating with the interiors of the cylindrical casing 23 are the fittings 24, each having an opening 25 therein commmunicating with a valve 26, which connects with the pipe 2? leading to a source of auxiliary gas such as coke oven gas. Coaxially disposed with respect to each cylindrical member 23 and the bore 22. is the pipe 28, supported by the struts 29a2$a. Each of said pipes 28'28 is provided with a valve 25 controlling communication with the oil inlet 39 and the steam inlet 3!. From the oil inlet 3% and the steam or compressed air inlet 31 a stream of atomized oil may be projected through the pipe 28 into the interior of the boiler it, having an aspirating effect in delivering coke oven gas from the pipe 27.

In its broader aspects the present invention may be considered without reference to the means fordelivering the auxiliary fuel through the bores 22 and the pipes 23. Referring for'the present only to the passageways for admitting blast furnace gas and air, the burner comprises I essentially a series of alternate air and blast furnace gas ducts. These ducts are defined in the forward portion of the burner by the rehave the function of retaining the refractory:

members l9l9 and 2| in position, serving as guides to define their location and to assist in holding them in place. The refractory members l9l 9 and 2 !-2I are readily replaceable, whereas the metallic portion of the burner, which is,

protected against damage, is of permanent construction.

An advantage accrues from the fact that the refractory members l9-l9 and 2l2l have substantial section as compared to the section of the metallic portion of the burner, and therefore occupy a considerable part of the face of the burner adjoining the combustion chamber of the boiler. As a result, the areas available for air ducts and gas ducts are somewhat restricted and are somewhat smaller than the corresponding duct areas in the back part of the burner which communicate with the gas and air inlets. This arrangement permits fairly high gas and air velocities to be used at the exit of the burner, while materially lower gas velocities are had in the rear portions of the burner where the gas must pass through certain turns and where it is desirable to avoid pressure drop. By reason of the construction referred to, the gas and air have relatiely low velocities where low velocity is desirable and have relatively high velocities adjacent to the boiler combustion chamber where. otherwise, difiiculties might be encountered due to flame propagation.

A very practical advantage accruing from the construction involving the refractory members 19-49 and 2I2l results from the fact that said refractory members form storage reservoirs for heat units, which reservoirs are maintained at high temperatures. In present day practice it is common to provide cooling walls for boilers,

which cooling walls are provided with water passages. Frequently the water withdraws from the combustion chamber such an amount of heat that in cases where the fuel feed is not great the flame will be extinguished, this result following from the fact that the furnace temperature is reduced below the temperature of combustion for the air and gas under consideration. This low rate of fuel feed is usually a transient condition, and if after the flame is extinguished a greater feed of fuel follows, this fuel may, according to prior structures, be delivered to the combustion chamber without being ignited, resulting in the accumulation of amixture of gas and air in the combustion chamber. If under such conditions the operator ignites this mixture, as for example by means of an oil flame, or other igniting device, he may cause a disastrous explosion.

According to the present invention, however, where the refractory walls provide high temperature reservoirs for heat units, the extinguishing of the flame will not occur. Even' in the event of low fuel feed, the ignition of the fuel with the air will be accomplished by reason of the incandescent refractory walls. These may be the only incandescent walls within the combustion chamber. The advantage referred to is furthered by reason of the fact that the passageways for gas and air adjacent to the furnace chamber are relatively narrow, resulting in the higher velocity of the gas and air, as above described. According to the present invention the velocity of gas flow may be readily maintained greater than the rate of flame propagation even when the rate of fuel feed is reduced to the minimum which the burner may be expected to supply.

A further advantage of the structure according to the present invention is that it is readily adaptable to different furnace dimensions in such manner as to enable most of the combustion chamber volume to be usefully employed.

, It is possible to occupy substantially the full width of a wall of the combustion chamber by a burner. Thus, the alternate layers of air and fuel are distributed over the entire horizontal area of the combustion chamber at the elevation corresponding to the burner, and the entire volume above this elevation is usefully employed for combustion space. This construction is to be distinguished from certain prior constructions in which a burner has been employed, in which the supply of blast furnace gas is more concentrated, certain portions of the furnace volume between burners or between such a burner and the walls not being well employed. The construction according to the present invention, be ing of the unit type, permits selection of a sufficient number of units for any desired furnace width. In case of very wide combustion chambers, it is possible to install two or more of the burners embodying the present invention in parallel.

Proceeding now to the discussion of the functions of the structure for delivering the auxiliary fuels, it is to be noted that the bores 22 and the pipes 28 are located, in each instance, below the passages 202[i for supplying the blast furnace gas. With this arrangement a plurality of alternate laminations of air and fuel are obtained with the fuels supplied. Furthermore, with the arrangement shown, the more buoyant fuel is located in the lower part of the burner. In other words, coke oven gas and the gas resulting from. the vaporization of the oil, being relatively light as compared with blast furnace gas, tend to mingle with the blast furnace gas delivered through the passageways 202fl. Air is delivered in laminations adjacent both to the blast furnace gas from the passageways 2020 and to the fuel delivered by the bores 22 and the pipes 28, whereby an efiicient mixture of fuel and gas is had.

Though a preferred embodiment of the present invention has been described in detail, many modifications will occur to those skilled in the art.- It is intended to cover all such modifications as fall within the scope of the appended claims.

What is claimed is:

1. In a burner, in combination, means providing alternate passageways for blast furnace gas and air, the rear portions of said passageways being defined by metallic portions of relatively small crosssectional area, the front portions of said passageways being defined by refractory members of relatively large cross sectional area, said refractory members at the lower portion of the forward extremity of said burner defining bores, means for delivering gas through said bores, said last mentioned gas being light relative to said blast furnace gas, and means coaxially disposed with respect to said bores for delivering atomized oil for mixture with said last mentioned gas adjacent to the forward extremities of said bores.

2. In a burner, in combination, means providing alternate parallel horizontally extending passageways for blast furnace gas and air, the rear portions of said passageways being defined by metallic members, the forward portions of said passageways being defined by refractory members having greater cross section than said metallic members whereby the cross sectional areas of said passageways adjacent to the forward extremity of said burner are small relative to the areas of said passageways at the rear of said burner, the bottoms of said passageways for said blast furnace gas being defined by refractory members providing bores, and means for delivering fuel through said bores, said air passageways being disposed in position to deliver air in proximity with the fuel from said bores.

3. In a burner, in combination, means providing alternate horizontally. extending passageways for blast furnace gas and air, the rear portions of said passageways being defined by metallic wall portions of relatively small cross sectional area, the front portions of said passageways being defined by refractory wall members of relatively large cross sectional area, said refractory members extending to the forward extremity of said burner and comprising reservoirs for heat as well as means for causing the speeding up of air and gases through said passageways to be discharged from said burner.

4. In combination, a combustion chamber, a burner, said burner embodying means providing a plurality of passageways for gas and a plurality of passageways for air, said passageways being parallel and alternately positioned and leading directly to said combustion chamber, said passageways at the forward portion of said burner being defined by refractory walls, said refractory walls being readily replaceable and being of such cross section as to provide reservoirs for heat at the forward extremity of said burner and formed to restrict the passageways therebetween for increasing the velocity of gas and air flow from said burner.

5. In a burner, in combination, metallic members of relatively small cross sectional area providing a plurality of alternate parallel passageways for gas and air, said metallic members including walls separating the gas and air passageways and extending forward to but stopping short of the forward extremity of said burner, the forward extremities of said metallic members terminating in vertically disposed members, said burner incorporating refractory members forming continuations of said walls and extending to the forward extremity of said burner, said refractory walls defining passageways for said air and gas of less cross sectional area than the passageways for said gas and air rearwardly of said refractory walls.

6. In a burner, in combination, means providing alternate horizontally extending passageways for relatively heavy gas and for air extending to the front face of said burner, means for delivering relatively heavy gas and for delivering air to said passageways, the rear portions of said passageways being defined by metallic members of relatively small cross sectional area, the front portions of said passageways being defined by refractory members of relatively large cross sectional area which separate said air passageways from said gas passgewys, said refractory members also defining'passageways for a more buoyant gas, means for delivering said more buoyant gas to said last mentioned passageways, said last mentioned passageways being located ata lower level than said passageways for said first mentioned gas.

7. In a burner, in combination, means providing horizontally extending passageways for relatively heavy gas and for air extending to the front face of said burner, means for'delivering relatively heavy gas and for delivering air to said passageways, the forward portion of said burner being defined by refractory members which define alternately disposed passageways for said relatively heavy gas and said air, said refractory members also defining passageways for a relatively light gas, means for delivering said relatively light gas to said last mentioned passageways, said last mentioned gas passageways being at a lower level than said passageways for said relatively heavy gas.

8. In a burner, in combinatiom means providing horizontally extending passageways for relatively heavy gas and for air extending to the front face of said burner, means for delivering relatively heavy gas and for delivering air to said passageways, the forward portion of said burner being defined by refractory members which define alternately disposed passageways for said relatively heavy gas and said air, said refractory members also defining passageways for a relatively light gas, means for delivering said relatively light gas to said last mentioned passageways, said last mentioned gas passageways being at a lower level than said passageways for said relatively heavy gas, and said air'passageways being alternately disposed with respect to both said relatively heavy gas passageways and said relatively light gas passageways.

9. In a burner, in combination, means providing horizontally extending passageways for relatively heavy gas and for air extending to the front face of said burner, the forward portion of said burner being defined by refractory members which define alternately disposed passageways for said relatively heavy gas and said air, said refractory members also defining passageways for a relatively light gas, said last mentioned gas passageways being at a lower level than said passageways for said relatively heavy gas, said air passageways being alternately disposed with respect to both said relatively heavy gas passageways and .said relatively light gas passageways, and means in said last mentioned passageways for delivering atomized oil through the exits thereof.

10. In a burner, in combination, means providing passageways for gas and for air extending to the discharge end of said burner, the forward portion of said burner being defined by repassageways and with respect to said oil delivering means.

ELLSWORTH J. WESTCOTT. JOHNC. HAYES, JR. 

